Against the backdrop of Pakistan's opposition to US drone strikes, UN chief Ban Ki-moon on Tuesday said the pilotless aircraft should be used only for gathering intelligence.
"As I have often and consistently said, the use of armed drones should be subject to long-standing international law, including the international humanitarian laws," he said.
Ban, who arrived in Islamabad on Tuesday a two-day official visit, made the remarks while addressing a gathering at the army's National University of Science and Technology.
His remarks are likely to strengthen Pakistan's lobbying to force the US to curtail drone attacks in its tribal belt bordering Afghanistan.
Rights groups have said hundreds of civilians have been killed or injured in US drone strikes. American officials have defended the use of the CIA-operated spy planes, saying top Taliban and Al Qaeda commanders have been killed in strikes.
Ban was speaking after launching a Center for International Peace and Stability at the university. The center will provide training for peacemaking efforts.
He appreciated the role of over 8,000 Pakistani troops deployed with peacekeeping missions under the UN auspices. "Pakistan?s engagement has been very crucial in peacekeeping missions," he said.
Director general of military operations Maj Gen Ashfaq Nadeem Ahmed said Pakistan was playing a leading role in establishing peace in the world and 136 of its soldiers had died while serving with UN missions.
During his stay in Islamabad, Ban will hold talks with President Asif Ali Zardari and Prime Minister Nawaz Sharif and discuss regional and international issues. He will also be chief guest at Independence Day celebrations on Wednesday.
Ban's visit coincides with the latest border crisis between Pakistan and India. There has been a spike in tensions after India said five soldiers were killed in an attack by Pakistani troops along the Line of Control.
State-run Radio Pakistan reported that Ban had expressed his grief over the violence in an interview and underscored the need for India and Pakistan to resolve the "long-standing" issue of Kashmir.